Transcriptional mechanisms by the coregulator MAML1.

The Mastermind-like (MAML) proteins are transcriptional coactivators for Notch signaling, an evolutionarily conserved pathway that plays several key roles in development and in human disease. The MAML family contains MAML1, MAML2, and MAML3. More recently, MAML1 has been shown to function as a coactivator for the tumor suppressor p53, the MADS box transcription enhancer factor (MEF) 2C, and beta-catenin. In addition, MAML1 has been reported to interact with the histone acetyltransferase p300, and this interaction increases p300 activity. Furthermore, MAML1 binds to CDK8, which is a subunit of the Mediator complex. The function of MAML1 as a coactivator for diverse activators, and MAML1 interaction with broadly used coactivators, suggests that MAML1 might be a key molecule that connects various signaling pathways to regulate cellular processes in normal cells and in human disease.